CN106544684A - A kind of cleaning surface of strip steel agent and its preparation and application - Google Patents

Abstract

The invention discloses a steel strip surface cleaning agent and its preparation and use method, comprising 20-25% of sodium hydroxide, 5-10% of sodium carbonate, 3-5% of sodium gluconate, 3.5-15% of anionic surfactant, non- The ionic surfactant is 0.5-10%, the chelating agent is 5-10%, and the water is 20-63%. The chelating agent is tetrasodium edetate tetrahydrate. The anionic surfactant is one or more of sodium dodecylbenzenesulfonate and sodium dodecylsulfate. The nonionic surfactant is one or more of alkyl polyoxyethylene ether and polyethylene glycol octylphenyl ether. Use this cleaning agent for the degreasing treatment of metal materials such as cold-rolled sheets and galvanized sheets to realize strip steel cleaning without pollutants, improve the cleaning effect and reduce costs; the cleaning agent should be replaced by tetrasodium ethylenediaminetetraacetic acid tetrahydrate The traditional phosphate acts as a chelating agent, which is safe and environmentally friendly; it can achieve the cleaning effect on the galvanized substrate, reduce the impact of strip surface pollutants on the subsequent galvanizing process, and improve the quality of galvanized products.

Description

A kind of strip steel surface cleaning agent and its preparation and use method

technical field

The invention relates to the field of strip steel surface cleaning agents, in particular to a strip steel cleaning agent and a preparation and use method thereof.

Background technique

Before galvanizing and color coating, metal sheets must undergo surface treatment processes such as degreasing to remove rolling lubricants, equipment miscellaneous oils, iron powder and other dirt on the metal surface. The degreasing degree of the metal surface will directly affect the follow-up of the strip steel. Handling quality. Therefore, the development of high-efficiency degreasing agent to improve the degreasing and cleaning ability of strip steel before galvanizing is a common concern in galvanizing production. Scholars from some units at home and abroad have made great progress in the research and application of the cleaning of oily pollutants on the surface of strip steel through continuous exploration, but the cleaning agents are mainly imported products, and their cost is relatively high.

Such as CN102220592A (foam-free slick type alkaline cleaning agent for pre-treatment of pre-coated steel plates), comprising the following components in percentage by weight: sodium hydroxide 10-25%, sodium carbonate 41-60%, sodium orthophosphate 10- 25%, sodium tripolyphosphate 3-15%, sodium gluconate 1-3%, polyether surfactant 5-15%, which contains phosphorus and pollutes the environment and has a higher cost.

CN101358355A (additive to non-phosphorus degreasing agent and non-phosphorus degreasing agent containing the additive) consists of raw materials in the following weight ratios: 0.6-4 parts of additive; 1-5 parts of self-defoaming emulsifier; 1-5 parts of surfactant ; 5-25 parts of sodium hydroxide; 1-5 parts of tetrasodium edetate; 1-15 parts of sodium carbonate; 0.1-15 parts of sodium silicate; 40-99 parts of water. The degreasing agent contains silicon components. If the surface of the strip remains, it will cause dezincification in the subsequent galvanizing process.

CN104711612A (normal temperature weak alkaline degreasing agent for galvanized workpiece and production method), the raw materials used and the mass percentage are as follows: 3-6% of cocoamidopropyl dimethyl ammonium oxide, 6-8% of sodium acetate, anhydrous sodium sulfate 1-2%, ethylenediaminetetraacetic acid 1-2%, soaking degreasing and degreasing special surfactant 3-6%, penetrating agent JFC 1-2%, water balance. Weak alkalinity will lead to reduced decontamination ability, and cleaning residues on the strip surface will reduce the efficiency of subsequent annealing and galvanizing processes.

CN103469232A (a degreasing agent composition), the chemical composition is calculated by mass percentage: alkali metal hydroxide: 20-35%, the second alkali source: 1-5%, inorganic degreasing aid: 1-10%, organic Degreasing aid: 1-10%, surfactant: 1-5%, defoamer: 0.5-5%, water: balance. The specific names of the various components in the degreasing agent are not clearly stated.

CN1804130A (a cleaning agent used for pretreatment of cold-rolled galvanizing), its components and weight percentages are: sodium hydroxide 10-50%, sodium carbonate 10-40%, polysodium phosphate 5-30%, glucose Salt 5-30%, complex alkyl phosphate surfactant 1-7%, polyether defoamer 1-7%. The combination of anionic and nonionic surfactants has a better cleaning effect on galvanized steel strips. In addition, it contains phosphorus and pollutes the environment and has a high cost.

Contents of the invention

In view of the above-mentioned defects, the technical problem to be solved in this invention is to overcome the prior art problem that the cleaning of the galvanized steel strip surface is not clean and cause the quality of the galvanized product, and to provide a strip steel surface cleaning agent and a preparation method thereof. High efficiency, good cleaning effect, and the use of compound production technology, normal temperature use, low foam, energy saving and environmental protection and other advantages.

In order to achieve the above object, the technical solution of the present invention is achieved in that:

A strip steel surface cleaning agent is composed of the following mass percentages: 20-25% sodium hydroxide, 5-10% sodium carbonate, 3-5% sodium gluconate, 3.5-15% anionic surfactant, nonionic Type surfactant 0.5-10%, chelating agent 5-10%, water 20-63%; The chelating agent is tetrasodium edetate tetrahydrate.

The anionic surfactant is one or more of sodium dodecylbenzenesulfonate and sodium dodecylsulfate.

The nonionic surfactant is one or more of alkyl polyoxyethylene ether and polyethylene glycol octylphenyl ether.

The mechanism and function of the components:

Sodium hydroxide: 20-25%, the main purpose is to saponify and remove oil to wet the surface of the steel plate. Sodium hydroxide can undergo saponification reaction with animal and vegetable oils to generate glycerin and soap, and glycerin and soap are easily soluble in water to remove oil stains. It has certain corrosiveness to metal, and its corrosion effect is weak;

Sodium carbonate: 5-10%, the main purpose is to act as an alkaline buffer and builder, to ensure the stability of the solution, and to improve the service life of the cleaning agent.

Sodium gluconate: 3-5%, can form coordination compounds with metal ions such as Fe, Ca, and Mg in the cleaning solution, reducing the possibility of these metal ions combining with fatty acids formed by saponification of oil to form metal soaps.

Anionic surfactant 3.5-15%, one or more of sodium dodecylbenzenesulfonate and sodium dodecyl sulfate, nonionic surfactants are alkyl polyoxyethylene ether and polyethylene glycol octane One or more phenyl ethers can play the role of improving detergency, solubilization, defoaming, emulsification and wetting. Sodium dodecylbenzene sulfonate or sodium lauryl sulfate is used in combination with two surfactants, alkyl polyoxyethylene ether or polyethylene glycol octylphenyl ether, for higher decontamination efficiency on metal surfaces.

Chelating agent 5-10%, tetrasodium ethylenediaminetetraacetic acid tetrahydrate as a chelating agent, its structure is a hydrophilic-hydrophobic link, strong emulsifying power, low cloud point, can be strongly adsorbed on the surface of the dirt, and improve the decontamination ability , and they are metal corrosion inhibitors, which can prevent metal corrosion.

A preparation method of strip steel surface cleaning agent, comprising the following steps:

1) Put water into the container first, and start the agitator;

2) Sodium hydroxide, sodium carbonate, sodium gluconate, and the anionic surfactant are put into the container in turn, fully stirred and mixed to dissolve the ingredients;

3) Put tetrasodium ethylenediaminetetraacetic acid tetrahydrate chelating agent into the container, fully stir and mix, and dissolve each component;

4) Put the non-ionic surfactant into the container, fully stir it, and pack it into a bucket after static aging.

The aging is not less than 1 hour.

A method for using a steel strip surface cleaning agent, the concentration is 3-7%, the balance is water, the treatment temperature is 45-60°C, the treatment method is soaking and/or spraying, and the treatment time is 1-3 minutes.

The cleaning agent of the present invention is used for the degreasing treatment of metal materials such as cold-rolled sheets and galvanized sheets, so as to realize strip steel cleaning without pollutants, improve the cleaning effect and reduce costs; the cleaning agent uses tetrasodium ethylenediaminetetraacetic acid tetrahydrate Instead of traditional phosphate as a chelating agent, it is safe and environmentally friendly; it can achieve the cleaning effect on the galvanized substrate, reduce the impact of strip surface pollutants on the subsequent galvanizing process, and improve the quality of galvanized products.

detailed description

Below in conjunction with embodiment the present invention is described in detail.

Example 1:

Sodium Hydroxide 15%

Sodium Carbonate 5%

Sodium Gluconate 2%

Tetrasodium EDTA Tetrahydrate 2%

Sodium Dodecylbenzene Sulfonate and Sodium Lauryl Sulfate 4%

Alkyl polyoxyethylene ether and polyethylene glycol octylphenyl ether 4%

Water 68%

First put the measured amount of water into the container and start the mixer. Put the measured sodium hydroxide, sodium carbonate, sodium gluconate, sodium dodecylbenzenesulfonate and sodium dodecyl sulfate into the container in turn, stir and mix thoroughly to dissolve each component. Then, put the metered tetrasodium ethylenediaminetetraacetic acid tetrahydrate chelating agent into the container, stir and mix sufficiently to dissolve each component.

Finally, put the measured amount of alkyl polyoxyethylene ether and polyethylene glycol octylphenyl ether nonionic surfactant into the container, stir well, and age it statically for not less than 1 hour.

When used in the production site, the concentration of this product is 5%, and the balance is water. The present invention is used for the degreasing treatment of metal materials such as cold-rolled sheets and galvanized sheets, the treatment temperature is 45-60°C, the treatment method is soaking, and the treatment time is 1-3 minutes.

Example 2:

Sodium Hydroxide 18%

Sodium Carbonate 8%

Sodium Gluconate 3%

Tetrasodium EDTA Tetrahydrate 3%

Sodium dodecylbenzenesulfonate 2%

Alkyl polyoxyethylene ether 2%

Water 64%

First put the measured amount of water into the container and start the mixer. Put the measured sodium hydroxide, sodium carbonate, sodium gluconate, and sodium dodecylbenzenesulfonate into the container in sequence, stir and mix thoroughly to dissolve each component. Then, put the metered tetrasodium ethylenediaminetetraacetic acid tetrahydrate chelating agent into the container, stir and mix sufficiently to dissolve each component.

Finally, the measured amount of alkyl polyoxyethylene ether nonionic surfactant is put into the container, fully stirred, and statically aged for not less than 1 hour.

When used in the production site, the concentration of this product is 4%, and the balance is water. The present invention is used for the degreasing treatment of metal materials such as cold-rolled sheets and galvanized sheets, the treatment temperature is 45-60° C., the treatment methods are soaking and spraying, and the treatment time is 1-3 minutes.

Example 3:

Sodium Hydroxide 20%

Sodium Carbonate 10%

Sodium Gluconate 4%

Tetrasodium EDTA Tetrahydrate 3%

Sodium Lauryl Sulfate 2%

Polyethylene glycol octylphenyl ether 2%

Water 59%

First put the measured amount of water into the container and start the mixer. Put the measured sodium hydroxide, sodium carbonate, sodium gluconate, and sodium lauryl sulfate into the container in sequence, stir and mix thoroughly to dissolve each component. Then, put the metered tetrasodium ethylenediaminetetraacetic acid tetrahydrate chelating agent into the container, stir and mix sufficiently to dissolve each component.

Finally, the measured amount of polyethylene glycol octyl phenyl ether nonionic surfactant is put into the container, fully stirred, and statically aged for not less than 1 hour.

When used in the production site, the concentration of this product is 6%, and the balance is water. The present invention is used for the degreasing treatment of metal materials such as cold-rolled sheets and galvanized sheets, the treatment temperature is 45-60° C., the treatment method is spraying, and the treatment time is 1-3 minutes.

The products made in Examples 1, 2, and 3 are used for the degreasing treatment of cold-rolled sheets and galvanized sheet metal materials. After the treatment, the surface of the steel strip hangs water evenly, the water film is continuous, and the cleaning effect is good. The invention has strong penetration and emulsification power to oil, and the degreasing rate reaches 98%.

The products made in Examples 1, 2, and 3 are used for the degreasing treatment of metal materials such as cold-rolled sheets and galvanized sheets, and the processed strip steel is processed according to the national standard "GB1771-91" Determination of neutral salt spray resistance of paints and varnishes", "GB1732-79(88) Determination of impact resistance of paint films", "GB1720-(79)88 Test method of paint film adhesion" to test them, in The permanent salt spray test reaches 400h, the impact resistance capacity reaches 50cm/kg, and the cross-cut test of coating adhesion is Class I.

Claims (6)

1. a steel strip surface cleaning agent is characterized in that it is made up of following mass percentages: sodium hydroxide 20-25%, sodium carbonate 5-10%, sodium gluconate 3-5%, anionic surfactant 3.5- 15%, 0.5-10% of non-ionic surfactant, 5-10% of chelating agent, and 20-63% of water; the chelating agent is tetrasodium edetate tetrahydrate. 2. The strip steel surface cleaning agent according to claim 1, characterized in that: the anionic surfactant is one or more of sodium dodecylbenzenesulfonate and sodium lauryl sulfate. 3. The strip steel surface cleaning agent according to claim 1, characterized in that: said nonionic surfactant is one or more of alkyl polyoxyethylene ether and polyethylene glycol octylphenyl ether. 4. a preparation method according to any one of claim 1-3 strip surface cleaning agent, is characterized in that comprising the following steps: 1) Put water into the container first, and start the agitator; 2) Put sodium hydroxide, sodium carbonate, sodium gluconate, and anionic surfactants into the container in turn, stir and mix thoroughly to dissolve the ingredients; 3) Put tetrasodium ethylenediaminetetraacetic acid tetrahydrate chelating agent into the container, fully stir and mix, and dissolve each component; 4) Put the non-ionic surfactant into the container, fully stir it, and pack it into a bucket after static aging. 5. The preparation method of strip steel surface cleaning agent according to claim 4, characterized in that: the aging is not less than 1 hour. 6. A method for using the strip surface cleaning agent according to any one of claims 1-3, characterized in that: the concentration during use is 3-7%, the remainder is water, and the treatment temperature is 45-60°C , the treatment method is soaking and/or spraying, and the treatment time is 1-3 minutes.